package com.wumao.service;

import com.wumao.mapper.CommentMapper;
import com.wumao.pojo.Comment;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Sort;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.util.ArrayList;
import java.util.Date;
import java.util.List;

/**
 * @author Gaowumao
 * @Decripted
 * @Email none-j@qq.com
 * @create 2021-04-19 9:31
 */

@Service
public class CommentServiceImpl implements CommentService {

    @Autowired
    CommentMapper commentMapper;

    @Override
    public List<Comment> listCommentByBlogId(Long blogId) {
        Sort sort = null;
        sort =Sort.by("createTime");
        List<Comment> comments = commentMapper.queryByIdAndParentCommentNull(blogId,sort);
        return eachComment(comments);
    }
    /*
    * 循环每个顶级评论节点
    * */
    private List<Comment> eachComment(List<Comment> comments){
        List<Comment> commentsView = new ArrayList<>();
        for (Comment comment : comments) {
            Comment c = new Comment();
            BeanUtils.copyProperties(comment,c);
            commentsView.add(c);
        }

        //合并评论区的各层子代到第一级子代集合中
        combineChildren(commentsView);
        return commentsView;
    }

    /*
    * @param  comments root根节点，blog不为空的对象集合
    * */
    private void combineChildren(List<Comment> comments) {
        for (Comment comment : comments) {
            List<Comment> replys1 = comment.getReplyComments();
            for (Comment reply1 : replys1) {
                //循环不迭代，找出子代，存放阿紫tempReplys中
                recursively(reply1);
            }
            //修改顶级节点的reply集合为迭代处理后的集合
            comment.setReplyComments(tempReplys);
            //清除临时存放区
            tempReplys = new ArrayList<>();
        }
    }

    //存放迭代找出的所有子代的集合
    private List<Comment> tempReplys = new ArrayList<>();

    /*
    * 递归迭代，剥洋葱
    * @param comment 被迭代的对象
    * */
    private void recursively (Comment comment){
        tempReplys.add(comment);//顶级点添加到临时存放集合
        if (comment.getReplyComments().size()>0){
            List<Comment> replys = comment.getReplyComments();
            for (Comment reply : replys) {
                tempReplys.add(reply);
                if (reply.getReplyComments().size()>0){
                    recursively(reply);
                }
            }
        }
    }


    @Transactional
    @Override
    public Comment saveComment(Comment comment) {
        Long parentCommentId = comment.getParentComment().getId();
        if (parentCommentId != -1) {
            comment.setParentComment(commentMapper.findById(parentCommentId).get());
        } else {
            comment.setParentComment(null);
        }
        comment.setCreateTime(new Date());
        return commentMapper.save(comment);
    }

}
